Wallet Playground for learning Bitcoin self custody with Piers Macrae | SLP767

**Stephan Livera** (0:00)
Hi, everyone, welcome back to Stephan Livera Podcast. Joining me on the show today is Piers Macrae from MineRacks. Piers recently made an interesting project, and I wanted people to learn a bit about it. It's called walletplayground.com.
So we're gonna chat about that this episode so people can learn a bit about self-custody. But yeah, first off, welcome to the show, Piers.

**Piers Macrae** (0:19)
Thanks so much, Stephan. Long time listener, first time guest.

**Stephan Livera** (0:24)
Well, thank you. Yeah, so, look, I know you're doing a lot of stuff around self-custody, self-custody education, and what I call self-custody consulting, right? There's kind of different models out there, right? There's kind of the model of like, obviously DIY, everything, do everything yourself. That's like the maximal kind of hardcore mode. And then there's, let's say like the CASA, Unchained, sort of nunchuck model. And then there's this model, which is you pay someone and they teach you, you know? They teach you how to do it. They kind of coach you how to do it. So there's different models to that. So talk to us a little bit about that and what you're doing at MineRacks.

**Piers Macrae** (0:58)
Yeah, I think there's a great distinction you just drawn there between, I guess, custodians. Collaborative custody is kind of like, help me do it for, well, partially it means do it for me, partially. Whereas self custody consultancy is kind of like, teach me how I can do it by myself and hold my hand along the way.
And so I guess wallet playground is sort of an artifact that's come out of the many years I've spent doing that work. It sort of scratched my own itch of there was, it was quite difficult to bring along my collection of hardware wallets and all of the different software that you can use to a conference or a workshop with lots of people attending. What would be an easy way to dematerialize all of that, to not have to take that much equipment with me as I travel around and do these workshops? And so I stumbled across a way of being able to simulate, basically having all the identical software. So the great thing with all of these wallets and all of the signing devices and the coordinating software is most of it is all open source or at the very least source available, which means that there's no technical barrier to someone taking all of that source code, running a firmware emulator on servers that then enables you to see that code interacting just as it would as if you had the real device in your hands right in front of you right now. And that's turned out to be quite a powerful training device.
In two scenarios. One, you might have a customer who's interested in getting eyes on all the different combinations of software that they could use on their desktop, and hardware they could use to secure their keys. But rather than having to purchase all of those pieces of equipment or borrow them from someone else to get eyes on and see which one is going to work for you, you have instead the ability now to just go to your web browser, type in a URL and at no cost, instantaneously get eyes on and hands on those very same tools prior to ever having to make a purchasing decision.

**Stephan Livera** (3:36)
Yeah, it's really cool. I was just playing around with it. Now, I will say there are times where it feels kind of a little bit clunky or it's hard to get certain hardware walls to connect to certain coordinated apps or software, but nevertheless a very useful and educational tool, because there are a lot of people who, for people like you and I who've been in the industry, and we've pretty much played around with every hardware wallet and used almost every coordinating software, it's kind of a different thing for us. But for somebody who's totally new, who's never played around with these things, it's a totally like, and the thing with some of these devices is they work in so many different ways. Like, as an example, the QR air gap flow is different to the micro SD card flow, which is again different to certain devices. Like, as an example, if you use Bitbox, you're kind of scrolling along the bottom or the top and like tapping it. And that's like, that is a different flow to like, oh, I've got my Trezor and I approve, you know, on the device. Like, it's just, we just have so many different devices in Bitcoin that are well known.
Talk to us a little bit about the diversity of the devices and, you know, how you go about teaching people when you're trying to teach people different self-custody hardware wallets.